Pneumatic conveyer



Oct. 30, 1934.. F, SCHICHT PNEUMATIC CONVEYER Filed Feb. 15, 1933Patented Oct. 30, 1 934 l UNITED STATES PATENT OFFICE 1,979,176PNEUMATIC CONVEYER Friedrich Schicht, Dresden, Germany ApplicationFebruary 15, 1933, Serial No. 656,911 In Czechoslovakia February 24,1932 3 Claims. (Cl. 302-36) This invention relates to improvements inpneueither lead to a stoppage thereof or else require matic conveyingplant, for instance compressed increased loading of the blower for thepurpose air conveyors for agricultural use, and its object of clearingthe conveyer pipe. is to reduce the power required for operatingAccording to the present invention these dis- 5 them and to increasetheir efiiciency. advantages are obviated by introducing the ma- Thedisadvantages of the methods and appaterial to be conveyed into the pipewith an inratus hitherto known for charging conveyers are trinsicvelocity which corresponds to the velocity mostly based upon the factthat the material to of flow of the conveying air at the point of inbeconveyed enters into the conveyor pipe with troductlon, this beingeffected preferably by 10 an intrinsic velocity which differssubstantially means of members which prevent fluctuations of from thevelocity of the conveying air, and that pressure at the introducingpoint resulting from ll t point Where the material t s e plan variationsin the quantity of material conveyed. particularly in the case ofirregular or interrupted For this purpose the material to be conveyed ishar in disturbing variations of p ure oc r seized by members fittedimmediately in front of 15 in the Co v y d Furthermore the theintroducing aperture, these members rotattroduction above all ofmaterial consisting of 111g revglving t th speed t which t individuallon fi r s t pr u p p a veying air flows past the introducing point, andhitherto occasioned great COIlStlllC'ElOIlEtl difilCllllgljveyjng thematerial into the conveyer pipe with ties and is associated with seriouslosses of efith Speed, 50 th t it passes i t th current of 20 ciency,mainly in consequence of losses of air, or air Without shocks or eddiesAS introducing throttling of its current and formation of eddies.members there are preferably emplgyed ll or If the material isintroduced on the suction side endless feeding belts arranged in pairswhich,

of the plant it experiences during its passag with their surfaces, whenrunning idly, close the through the blower a comparatively high accelerfeding aperture, and rotate or revolve in Opp)- ation, so that in tfurther eehveyel it has to site directions against the introducingaperture,

be braked down to a mueh lower Cenveying speedso that they seize thematerial between them by This however brings with it a defectiveutilizaa nipping action and dell-vent into t pipe The 61011 of thedriving power- The P- of the rollers or belts may be resilientlysupported or material beyond the blower, that is to say, on the may beprovided th a siliently yielding cov- 30 pressure side of the plant,requires a marked en-ng, of indiarubber for example By the particonstriction of the pipe before the point of introciss of materialsintroduced for conveyance, the

auction for the purpose of bringing a h feeding members bearing againstone another are injector action that sucks the material tnat is onlyqeparated from one another to be conveyed into the pipe. Thisconstriction and for the time Om involves a marked throttling of thecurrent of duced between them is fined up with the mate gg fifi g gzii gggij gl ff g ggg fig sf rial that is being conveyed. An equalization ofThe conveying air must under these circumstances accelerate the materiallying in the filling 40 pp from a state of rest up to the Conveyingprecluding losses of conveying arr, so that the Speed and this resultsin pulsations and irregw steadiness of the current of conveying air isnot larities in the current of conveying air, and reimpaired any ducesthe efiiciency of the plant. The conditions Three dlfierent examples ofthe construction are similar when the material is introduced ofapparatus acFording t0 h invention a e dia- 45 through nozzles, whichare charged for example grammatically illustrated in sectional elevationby a current of air branching off from the blower. in Flgllles l, 2 and3 0f the aeeempahying d awi In both cases the pressure conditions varyin the In the Constructlon shown In 1, he introintroducing apertureitself as soon as suppledlleihg aperture 1 0f the pressure p p 2 iSSealed mentary air alone or with a greatly varying quany the rollers 4and 5 l d in the as 50 tity of material to be conveyed enters throughthe these rollers rotating With a p p a Speed said aperture owing totemporarily interrupted equal to the p d With W h h C vey ng air orirregular feeding of the material. These sudfi W p th ap u e The roller5 is rockden variations in pressure give the material inably suspendedon a link 8, and is pressed by a troduced a tendency to settle down,whenever p ng or the like against the roller 4. The work- 55 thepressure falls, at the bends in the pipe, and ing surfaces of therollers may be covered with V used without lower belt conveyer l1,

indiarubber or the like, and are suitable for introducing even materialwith long fibres, such as straw or the like, which can be thrown ineither continuously or intermittently.

In the construction shown in Fig. 2 the material is introduced by twofeeding belts 9 and 10, running round roller 6, '7 respectively. Thelower guide roller 7 of the front belt conveyer swings on a link 8, sothat the belts 9 and. 10 when running idly, bear against one anotherwith their front ends, and seal the introducing aperture 1 of theconveying pipe 2. The material seized by the belt conveyers by a nippingaction and driven towards the pipe raises the guide roller '7 of thebelt conveyer 10 and opens the aperture 1 for the time of its passage,but at the same time shuts off the gap between the belts from theatmosphere.

In the construction according to Figure 3, the running round rigidly orresiliently mounted guide rollers 6, is made of either resilient orunyielding material, and closes the introducing aperture 1 throughoutits entire extent. When a portion 12 of the material to ,be conveyedpasses through underneath the lower end of the unyielding belt conveyer9 running round guide rollers 6, it forces its way so far into theyielding belt 11 that its upper surface lies flush with the surface ofthis belt. The ,material accordingly passes through into the conveyingpipe 2 without an open air gap having been produced, through which anyconsiderable quantities of air could pass.

In all the constructions the introducing memgbers deliver the materialthat is being conveyed into the conveyer pipe with the same intrinsicspeed and direction with which the conveying medium flows past theintroducing aperture.

The same constructions also admit of being alteration for suction airconveyance, without requiring any provision for preventing the entranceor escape of subsidiary air.

By suitably dimensioning the introducing members and by regulating thedriving thereof, in dependence upon the driving of the blower ifdesired, it is further possible with all these constructional forms toadapt the speed of introduction of the material that is to be conveyedto the actual speed of the conveying air in a continuous manner.

What I claim is:

1. Means for introducing into the conveying pipe of a pneumaticconveyer, through a charging aperture in the said pipe, the material tobe conveyed, comprising a pair of endless feeding belts revolving inopposite directions and bearing yieldingly against one another at apoint close to the charging aperture, the said feeding belts beingadapted to seize the material with a nipping action and move itpositively into the conveying pipe, while preventing admission andescape of air at the point of introduction, and also adapted at the sametime to impart to the material an intrinsic velocity approximatelycorresponding to the velocity of conveyance at this part of theconveying pipe.

2. Means for introducing into the conveying pipe of a pneumaticconveyer, through a charging aperture in the bottom of the said pipe,the material to be conveyed comprising a pair of endless feeding beltsrevolving in opposite directions and bearing yieldingly against oneanother at a point close to the charging aperture, the said feedingbelts being adapted to seize the material with a nipping action and moveit positively into the conveying pipe, and also adapted at the same timeto impart to the material an intrinsic velocity approximatelycorresponding to the velocity of conveyance at this part of theconveying pipe, the operative side of one of the belts closing thecharging aperture so as to prevent admission and escape of air at thepoint of introduction, and forming the floor of the pipe at that point.

3. Means for introducing into the conveying 110 pipe of a pneumaticconveyer, through a charging aperture in the said pipe, the material tobe conveyed, comprising a pair of endless feeding belts revolving inopposite directions and bearing resiliently against one another at apoint close to the charging aperture, the said feeding belts beingadapted to seize the material with a nipping action, accelerate it up tothe speed of conveyance and move it positively into the conveying pipewith this speed, and the operative side of one of the belts moving inthe direction of conveyance and closing the charging aperture so as toprevent admission and escape of air.

FRIEDRICH SCHICHT.

